Sewing looper mechanism



June 2, 1936. F. N. Ross l-:T A1.

SEWING LOOPER MECHANISM Filed Oct. 20, 1930 13 Sheets-Sheet l June 2, 1936. F N R055 ET AL 2,043,064

SEWING LOOPER MECHANISM Filed Oct. 20, 1930 13 Sheelbs-Shee'rI 2 INVENTORS wmwwmwww,

ATTORNEY June 2, 1936.

F. N. Ross ET AL 2,043,064

' SEWING LOOPER -MECHANISM Filed Oct. 20, 1930 15Sheets- Sheet 5.

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SEWING LooPER MECHANISM Filed oct. 20, 1930 13 Sheets-sheet 4 ,4. y MQN .v .-..HHWKPNN 1M L. 1mm 4 A VIII MNHN.. N`\\\ DE 1 u l A i xm June 2, 1936. F. N. Ross ET A1. 2,043,064

SEWING LOOPER MECHANISM Filed oct. 2o, 1930 1s sheets-sheet 5 ATTORNEYJ` June 2, y1936. F N, R055 ET AL 2,043,064

SEWING LOOPER MECHANISM Filed 0st. 20, 1930 l5 She'etS-Sheet 6 w .NVENTORJ ATTORN EYS June 2, 1936. i F N, Ross ET AL 2,043,064

SEWING LOOPER MECHANISM Fld OC.. 20, 1950 l5 Sheets-Sheet 7 ATTORNEYS MMM/Md wkn/@ALM June 2,1936. F N, OSS ET AL 2,043,064

SEWING LOOPER MECHANI SM Filed oct. 20, 1930 15 Shets-Sheet 8 f//f/ zj/V 2f/0 /QMZ' a? INVENTORS ATTORNEY 5 June 2, 1936. F. N. Ross ET A1.

I SEWING LOOPER MECHANISM 13 Sheets-Sheet 9 Filed Oct. 20, 1930 ATTORN EY,

June 2, 1936. F. N. Ross ET AL SEWING LOOPER MECHANISM Filed Oct. 20, 1930 13 Sheets-Sheet 10 June 2, 1936. F, N. Ross ET AL SEWING LooPER vMECHANISM 13 sheets-sheet 11 Filed Oct. 20, 1950 ATTORNEYS June 2, 1936.

F. N. ROSS ET AL SEWING LOOPER MEQHANI SM Filed Oct. 20, 1930 15 Sheets-Sheet 12 wwmM/b ATTORNEY-f June 2, 1936. F. N. Ross ET Al.

SEWING LOOPER MECHANISM Filed Oct. 20, 1930 l5 Sheets-Sheet 13 ATTORN EYS Patented 2, 1936.

UNITED s'rA'rEs SEWING mm MECllANISM Y Fredu'lek N. Bols and Horace L. Johnson, Def

. trait, Ilich., allignors. by

to- Briggs llanuf corporation of Michigan October 2l, 193., Serial 110.199,84 A

meme assignments Company, Detroit s camu (ci. 1in-191) Tnisinventlonrelatestoamethodandapparatus of manufacturing upholstery for seat cushionsandthelikeandmoreparticularlytoan improved .of sewing emplaying a threaded thrusting and retractin'g needie and-a threaded reciproting'looper. `Thisisacolnpanioncaseto ourapplication, SerialNo. 400,31'l'and relatingeneraltoasimilarmeans for'andmethod of producing tubular lo'upholstery. As a this presentin- Aventionhilsasoneotitsirnportant objectsto eliminate all o! the known objections to heretoforeknowntypesotautonmticupholstery manufacturing m and to produce automatic l5 and continuous upholstery having the characteristics of the heretofore known manually executed methods of upholstery manufacture. i

'Ihe several objects, advantages and novel details of construction of the invention together with the combination and arrangement of parts and the manner in which our improved method is carried into execution .will be`msde more apparent as this description proceeds, especially when considered in connection with the accompanying drawings. wherein Figure l is a fragmentary side elevational view of a portion oi an upholstery sewing machine constructed in accordance with our invention;

Figure 2 is an enlarged fragmentary perspec- 'tive view of the sewing mechanism of the machine; 1

FigureBisasimilar view ofthesewingmech-o anism as viewed from the other side of the machine, certain of the parts being broken away to show interior construction:

Figure i is an enlarged fragmentary vertical sectional view through the sewing mechanism showing the adjacent associated parts including the finish and lining fabric formation mechanism and the cotton bat feeding mechanism; n

Figure 5`is an enlarged fragmentary horizontal sectional view takenv substiitntlally on the plane indicatedbythelineBf-linl'igure llookingin the direction of the arrow; Y

Figure dis a vertical sectional elevational view taken substantially on the plane indicated by line 8 8 in Figure 5; e Y Y Figurelisafragmentarysectionalview through a portion ot the looper driving mecha- ""nism teken substantially ontheplsne indican ed by line 'i-l inF'lgllreS;

Figure 8 is an elevational view as viewed sul); stantially on the line 8,-! of Figure 4 and inthe direction of the arrow;

K Figure 9 is a l longitudinal sectional view through a portion of the looper mech- -anism taken substantially on the plane indicated by line -l in Figure 8;

Figure 10 is a transverse sectional view taken substantially on the plane indicated by line Il Il-il in Figure 9; v

Figure 1l is a transverse sectional view taken substantially on theplane indicated byline il-li in Figure 9;

Figure 12 is a sectional view taken substan- 10 tially on the plane indicated by line Ii--ll in Figure 9;

Figure 13 is a sectional elevationar view taken substantially on the plane indicated by line -Il in Figure 4; 15

Figure i4 is a perspective view'ot a portion of the looperl housing; t

' the lining and nnish fvlrics and tpe cotton but 3' are presented to these ng mechanism;

Figure 18 is aL fragmentary front elevational f view oi one of the sewing heads and its supporting mechanism; Y

Figure 19 Vis a vertical sectional elevational view 35 taken substantially on the line |8l9 of Fig. 18:

Figure 20 is a fragmentary horizontal sectional view taken substantially on the plane indicated by line 20-20 in Figure 19;

Figure 21 is a vertical sectional elevational viewy 40 taken substantially on the plane indicated-byline l l-liinFlgure 19;

Figure 22 Ais a sectional elevational view taken substantially on the plane indicated by line 22e-22 m nsurev19; Figure'23 is a fragmentary vertical sectional A looking inthe direction or the arto/ws view taken substantially Vou '2i-23 in Figure 18;

Figure 24 isan enlargedf'vertical transverse 50 i sectional elevational view throughthe apparatus at tire sewing point of the sewing heads showing Y two of the sewing heads fragmentarily and the Vmechanism for presenting theiinish and `lining fabrics and cotton bat to the sewing- 55 es V together with the section through the tubular formation;

Figure 25 is a side elevational viewV of the looper;

Figure 26 is a top plan view of the looper;

Figure 27 is an end view of the point end of the looper;

Figure 28 is a vertical sectional view through the looper taken substantially on the plane indicated by line 28-28 in Figure 26;

Figure 29 is a semi-diagrammatic view showing graphically the movement of the needle arm and needle together with its operation mechanism with respect to the seam and the looper, the two extreme positions and two of the intermediate positions of the needle and needle arm being indicated respectively by light lines, heavy lines, dotted lines, and dot and dash lines;

Figure 30 is a diagrammatic view graphically illustrating the relative positions of the looper and needle when the parts are in the position shown by black lines in Figure 29;

Figure 31 is an elevational view showing the sewing head and the looper in the position shown in black lines in Figure 29 Figure 32 is a diagrammatic view showing graphically the position of the needle and looper in the dotted line position illustrated in Figure 29;

Figure 33 is an elevational view showing the sewing head and the looper in the position shown in dotted parts in Figure 29;

Figure 34 is a diagrammatic'view illustrating graphically the position of the needle and looper in the light line position shown in Figure 29;

Figure 35 is an elevational view of the sewing head showing the parts in the position illustrated by light lines in Figure 29;

Figure 36 is a diagrammatic view showing graphically the positions of the needle and looper as illustrated in dot and dash lines in-Figure 29;

- Figure 37 is an elevational view of the sewing head showing 4the parts thereofJin the'position illustrated in dot -and dash line position in Figure 29;

Figures 38 to 45 inclusive are semi-diagrammatic perspective views of the needle and looper showing the development of the stitches;

Figure 46 is a fragmentary sectional perspectivle view of the completed stitching as viewed from one side of the seam;

Figure 47 is a similar view asviewed from the other side of the-seam; l

Figure 48 is a semi-diagrammatic view showing the manner in which the finish and lining fabric are arranged during the sewing operation, an

Figure 49 is a similar view of the completed upholstery, with the cotton bat omitted, with the lining fabric stitched taut.

Referring rst to Figures 48 and 49, the general problem involved will be explained. In these figures the finish or top fabric of the cushion or upholstery is indicated by the reference character F and the bottom or lining fabric is indicated by the reference characterL. It will be understood that these fabrics are united in the machine with the lining Vor bottom fabric on top.

It is the purpose of this invention to provide a method and means for uniting the finish and lining fabrics to provide a plurality of plaits or tubes with the stitching extending from the outside of the lining fabric into the interior of the tubes where the stitching is completed. In accordance with this invention', the finish fabric is gathered )to provide a plurality of spaced parallel tucks or folds S and the lining fabric is arranged in superposed relation over the finish fabric with portions L' adjacent to and parallel with the folds S at one side thereof. The lining fabric is spaced from the folds at the other sides thereof to produce clearance spaces X for the looper and needle to enable the completion of the loop of the stitch within the completed tubular forma-r tion 'I'.

'I'he finish and lining fabrics are united by transverse stitching Y extending from the outside through the portions L of the lining L and through the folds S of the finish fabric F, the loopers, yet to be referred to, working in the spaces X and the needles extending from the exterior of the tubes into the spa'ces X where the chain or loop of the stitches 'is completed.

When the upholstery is subsequently applied to the seat, the lining fabric L is stretched taut but as will be noted from Figure 49, no strain whatsoever will be imparted to the stitching Y because with the herein described method of stitching, seam ridges are not produced in the'lining material. Moreover, the stitching is substantially invisible on the face of the complete upholstery and in this respect the finished upholstery is substantially the same as that constructed by the 'heretofore known manual methods of manufacture. By reference to Figure 1, the drive mechanism for the several parts of the apparatus will be described. .The reference character` 50 indicates a motor through which abelt 5I drives a pulley I2 which may be coupled to shaft 53 by means of a clutch mechanism 54 controlled by lever 55. The shaft 53 is connected to a reduction gearing contained in housing 56. Through this reduction gearing a main shaft-51 is driven. This shaft carries a sprocket wheel with which a chain Il engages, this chain passing an idler 59 and then around a sprocket wheel 60 which drives the cloth or finish fabric forming mechanism. The chain also passes around a sprocket 6| on the drive shaft of the lining or foundation forming mechanism and lthen around a sprocket 62 which drives the cotton bat feeders. From this latter sprocket the chain passes a sprocket wheel 63 which drives the front roll of the machine. Obviously, all of these parts are driven in timed relation at a reduced 'speed in accordance with the reduction gearing contained in the housing 56.

Mounted on the shaft 53 is a sprocket wheel il which is connected by'means of .a sprocket chain 65 to a sprocket wheel 86 contained in a housing 6l,v see more particularly Figures 5 and 6. 'I'his sprocket wheel 66 is rotatably loosely mounted on a shaft 10 with which it may be connected for rotation therewith by means of a clutch 53 comprising a hub splined on the shaft 10 and normally urged into clutching position by a spring 68. 'I'he shaft 'I0 carries a bevel pinion 1i meshing with a bevel pinion 12 on a shaft 13. This shaft 13 is the drive shaft for the sewing heads yet to be referred to.

When it is desired to stop the operation of the sewing heads the clutch il!!v is disengaged by permitting clutch control pin 14 to engage in the cam groove l5 of sleeve 76', splined on shaft 68. The clutch control pin il is normally urged in a downward direction by a spring 17 and may be permitted to engage the cam 'groove 15 by rotating the clutch c'ontrolpin to permit the transverse` pin 78 to enter a slot (not shown) in the sleeve or bushing which surrounds the pin 14 adjacent the 75 to and parallel with the fold S at one side thereof,

transverse pin 18. Engagement of the pin 1I with the cam porti'on of the groove 1 5 inthe clutch hub, when the latter is rotated, causes said clutch hub to be withdrawn from clutching engagement with the sprocket 66, permitting the latter to run free.

The sewing head driving shaft 18 is provided with an eccentric 19 to which a pitman rod 88 is connected, see particularly Figures 5 and '1. This pitman rod is connected to an arm 8| keyed to a looper drive shaft 82 so that rotation of the sewing head drive shaft 13 will cause an oscillation of the looper drive shaft 82.

By reference to Figures 2, 3,. 4, 15, 16 and 24, the means for presenting the finish and lining fabrics to the sewing mechanism and the manner in which these fabrics are presented to the sewing mechanism will be .more apparent; The finish fabric F is fed to the sewing mechanism by means of an endless conveyer 83 which is provided with a pluralitvof upstanding bifurcate'dprojections.

84 (see also Figs. 15, 16 and 1'?)l which inthe upper ight ofthe conveyr 83 will produce a plurality of longitudinally extending spaced parallel ribs which gather the nnisn fabric F to produce/tucks or folds S.

The lining fabric L is fed downwardly from above between stationary formers 85 and drivenchain members 88, which cooperate with the stationary formers 85 to form the lining fabric and to feed the same to the sewing mechanism. By means of the lining fabric forming mechanism 85- 88 the lining fabric L is, presented to the sewing lmechanism with portions thereof lying adjacent to and parallel with the tucks or folds S at one side thereof as previously described inconnection with Figure 48 and as clearly illustrated in Figure 24.

The folds S formed in the finishy fabric F are presented over vertically arranged sewing plates 81 (see particularly Fig. 16) the ends of which are embraced by the bifurcated projections 84 and receive the folds therefrom. Said folds S are maintained with respect to each sewing plate 81 by means of forming feet 88 and 89 arranged on opposite sides of the sewing plate as most clearly illustrated in Figure 24. The feet of each pair are bifurcations of va member 98 which is adjustably connected to a beam 9| (see particularly'Fig. 4) which extends transversely of the. machine and constitutes a stationary'part thereof.V

The members 98 are secured tothe beam 9| for adjustment transversely of the machine so that the spaces between the seams may be varied as desired and for this purpose the beam 9| is provided with a transverselytextending T -shapm slot 92 and the members j98 are provided with adjusting bolts 93 by means of which these members may be secured in place.

Cooperatingwith each sewing plate 81 and carried by thefrespective sewingmechanismis a shouldered platemember 94 having a vertically extending flange portion 95 which lies adjacent to and parallel with the upper margin of the sewing plate to hold the lining fabric L adjacent for instance, as is clearly illustrated in Figure 24.

Each member 98 has a section 96 of the corresponding looper' housing attached permanently' v permanent section 96 of the looper housing terminates ashort distance to the right of the sewing section.

mechanism as viewed in Figure 4, and the rear edge of this stationary section 98 is preferably inclined as at 98 (Fig. 3) to coperate with a similarly inclined end 98 of the removable housing Thus, relative vertical .movement be. 6 tween the meeting ends 98 and 98 ofthe housing sections is prevented when the removable section has been secured in place. As seenprobably most clearly in Figures 16s and 24, each sewing plate 81 is provided with an l0 open end slot |88 providing a passage through the sewing plate for the needle of the associated sewing mechanism and the feet or plate members 88 and 95 are provided with registering apertures and |82 for the needle.

description of Figure 48; This guard acts as a barrier to prevent the cotton bat C from becoming entangled with the needle point. 'The sewing plates 81 extend between the bib 30 furcations 88 and 89 of the member 98 and act, as heretofore mentioned, to receive the folds S presented thereto by the finish fabric formers 84. While the bifurcations 88 and 89 which provide the .formers or feet for maintaining a fold 35 on the corresponding sewing plate 81, are mounted at their left hand end as viewed in Figures 4, 15 and 16, and extend toward the right in the direction`of the movement of the .nish and lining right hand ends and extend between the bifurcations 88 and 89 in a direction opposed to thetravel of the finish and lining fabrics. As has been previously described, the formers 488 and 89 are mounted as a unit for adjustment transversely of 48 the machine to vary the distance between adjacent seam ridges, so also the sewing plates are".

mounted as to be capable of transverse adjust-v A ment for a like purpose. The manner in which this is accomplished is best illustrated bya com- |50 parison of Figures 2, 3, 4, 15 and 16. From these figures itwiil be noticed that each sewing plate 1 81 is secured by means 'of a bracket |05 onto'a' y cross. beam |66 extending transversely ofthe machine. This bracket is provided witha T-shaped 55 Y slot |81 with which an adjustment bolt |89- cofabrics F and L respectively are presentedto the r sewing mechanism associated and arranged with respectto one another as clearly illustrated in Figure- 24 whereby the needle of each sewing 65 mechanism may have a thrusting and retractingj movement through the fold in the flnishfabric and the parallel portion of Athe lining fabric at substantially right angles to the longitudinal center of thefoid. v '-70 Bg reference particularly to Figures 3, 4, '1, 8, 9, 10, 1'1, 13, 14, 15 and 25 to 28 inclusive, the loope'r mechanism'andthe operating means therefor willbe described. As previouslymentione'd the looper housing consists of a stationary sec- 75 Coincident with the 15. arirture Ill is a pair ofopposedapercures m in fabrics, the sewing plates 81 are mounted at their 'flexible shaft or piano wire |28 tion 88 and a removable section 81. This latter section rests upon and is supported adjacent the transverse beam 8| of the machine and as shown in Figure 14, the housing section is provided with a backing plate |88 which at its upper end can-ies a bracket ||8 slotted as at and at its lower end carries a tongue |2. As shown in Figure 4, the backing plate |88 rests against the beam 8| and in positioning the same in place the tongue ||2 engages a locating slot ||8 lformed in the upper face of the member 98, see particularly Figures 4 and 15. In connection with Figure 15 it will be notedthat the top half of this figure shows the looper housing in place while the lower half of this figure shows the looper housing removed.

The upper end of the looper housing is enlarged as at ||4 to telescopewithin the lower end of a tubular member I I5 which latter is provided with a bracket ||8 adapted to be adjustably connected to a substantially horizontally arranged portion 8| of the bracket 8|. For providing for this adjustable mounting, the bracket portion 8|' is formed with a T-slot with which the clamping bolts ||8 iengage.

Each bracket ||8 has a portion ||8 which constitutes a bearing Support for the looper shaft 82 and keyed to this shaft 82 are a plurality of levers |28, one for each looper mechanism. 'I'he key |2| for the lever |28 permits of adjustment of lever |28 with respect to the shaft 82 longitudinally thereof but prevents relative rotation of the shaft.

The looper |22 shown in Figures 25 and 26 is adapted to be reciprocated in its housing by means of a flexible shaft 28 in the form of a piano wire. This wire |28 is enclosed in a iiexible guide housing |24 supported at longitudinally spaced pointsV in the housing 88-91 by means of guides |25. Each of these guides |25 is apertured to permit the passage therethrough of the thread T. The piano wire |28 extends up into the tubular housing f ||I and is clamped as, for instance, by means of set screws |28`to a reciprocating head |21 which is adapted to be reciprocated in the tubular housing ||5. This head |21 has a lug or ear |28 ex tending laterally therefrom through a slot |28 in the housing ||5. A link |30 is pivotally connected to the ear |28 as at |8| and is pivotaly Aconnected as at |82 to the lever |20. Thus oscillation of shaft 82 causes a rocking movement to be imparted to lever |28 which through link |88 will reciprocate the head mand through the will reciprocate the looper I 22.

'.'lhe head |21 is guided during its reciprocating movement by the housing ||5 and is also provided with a longitudinal opening or bore capable4 of receiving a tubular thread guide |38.A The thread T previously referred to passes in through /of the thread is drawn' out of the'vaperture |52 the longitudinal bore |84 of the thread guide |88 and then through the housing and through the .apertures of the guides |25 previously referred to.

The lower end of the thread guide tube |88 is provided with an enlarged portion |85 which ilts snugly within the tubular housing I|5 to locate the lower end of the guide therein, this enlarged portion also providing means for securing the end |24' of the flexible guide housing |24 of the piano wire or flexible shaft |22.

The upper end of the thread guide |88 is provided with a knob or handle |86 which is adapted to engage the ared upper end of the guide housing ||5 and for preventing accidental removal of the thread guide tube `|88 we provide a spring 'passed-first through the a, ,oca

latch |81 having a latch shoulder |88 adapted to snap over an annular flange |88 on the knob |88. The link 188 is detachably connected to the ear or lug |28 by means, probably most clearly illustrated in Figure 12. The pivot |3| is carrligd by a plate |48 and is capable of being lateral withdrawn from engagement with the lug |28 by means of a handle |4|. The plate |40 is drawn laterally away from the link 80 against the action of a spring |42 acting on a headed pin |48. The pin |44 is merely a guide. The knob |4| is grasped and' pulled toward the right as viewed in Figure 12, which action withdraws the pivot 8| from engagement with the ear or lug |28 so that the operative connection between the link |80 and the reciprocating head |21 may be disconnected.

' When this link has thus been disconnected the latch |81 may be actuated to release the knob |88 whereupon this knob together with the guide tube v|88,"the reciprocating head |21 and the looper operating shaft-|28 together with its guides |24 and the looper |22, may be withdrawn from within the looper housing 88-91. 'I'his is for the purpose primarily of threading th'e looper which is to be accomplished in a manner to be hereinafter more fully referred to although obviously the looper mechanism may be withdrawn as just described for the purpose of replacing worn parts or replacing broken parts.

'I'he looper or looper head is illustrated in side elevation and top plan view respectively in Figures 25 and 26, in end elevation in Figure 27 and in section in Figure 28. By reference tofFigures 25 and 26 and alsoposslbly to Figure 38, the construction of the looper itself and of the manner in which it is initially threaded and subsequently carries the thread will be apparent.

'Ihe looper |22 is provided .with a depending portion or projection' |45 longitudinally apertured as at 481: receive the end oi' the actuating shaft or wire |28 which may be' secured theretoby means oi' a pin |41. 'I'he point |48 of the looper is apertured as at |48 and the body of the looper is provided with a transverse aperture |50. 'The aperture, |58 extends transversely of the looper and the-apertures v|48 vertically with respect to `the point |48. The top surface of the looper is provided with a longitudinal groove and with a communicating vertically inclined aperture |52. As will be seen from Figure 38 the thread is transverse aperture |58 from the far side as viewed in Figure and out through the near side of this aperture4 and thenA over the point |48 and up through the vertical aperture |48, then back through the groove |5| and downwardly through the inclined aperture |52 and out through the near side of the looper wher'eqthe free end is left. After a few stitches, as will be apparent from an examination of the successive Flsures38 to 45 inclusive, the free end and groove |5| but always remains threaded through the point at |58 and |48.

The transverse cross-section of the' looper is such that it fits within and is guided for reciprocation within the housing which is ci substantially the same cross-section but inl order to provide y relief for the looper'and to lreduce the surface contact between the looper and housing, the verl tical sides of the .looper which are the'greatest' cross-section are relieved as at |54.

I'he looper4 as will be obvious, is reclprocated withinthe housing in a plane at right angles to the plane of the thrusting and retracting movement of the needle, yet to be referred to, and in e path which intersects et right angles the peth or i the needle. The looper is reciproeated in a lplane substantially parallel with and adjacent to the longitudinal vertical plane of the tuck or fold SQ The looper is also reciprocated within the plait or tube formed by the finish and lining fabricsl F and L and this permits the formation and completion of the stitch interiorly of the plait`or tube in a manner be more fully hereinafter de-V scribed. i

The reference character |55 indicates a transverse beam or frame portion of the machine upon which the sewing heads are mounted. Obviously, there is one sewing head for each looper mechanism and a number of sewing heads corresponding to the numberfof folds S presented to the sewing mechanism. Each of the sewing mechanisms which includes means for imparting a combined thrusting and retracting `and rocking movement to the needle is supported on the sewing head shaft 15 and by a pair of depending brackets |55. 'Riese brackets which are substantially inverted L-shaped-are addustably secured to the lower face of the beam or frame member by means ofclamping bolts |51 which engage substantially T-shaped slots |55' formed in the beam |55. Each bracket member |55 has an c inwardly' extending sleeve |55 which surrounds the shaft 15, the endsof these sleeves abutting against opposite sides of the driving pinion |55.'

.A This pinionv |55 is keyed to the shaft 15 by a key |5 working in a longitudinal key-way |52 in the shaft so that the pinion will rotate with the shaft but will be capable of longitudinal movement thereonwhen adjusted.v i

Thesewingheadhasamainbodyorbracket pei-i: m whiehis provided at its upper end with semi-circular tubular bearing extensions |54 engaging the' sleeves |55 and with a central semicircular recess |55 enclosingfthe lower half of the pinion |55. The bearing extensions |54 and the pinion enclosure |55 are completed by a capwhich has corresponding portions, this bearing cap beingv pivotally connected to the main body bracket |55 as at 51 and being secured in place as,- for instance, by -meansof a bolt |55;

Therefore, the sewing head bracket |55 is mounted upon `the main supporting brackets |55 and may be adjited longitudinally 0f the shaft 'Il when the brackets |55 are adjusted.

In order that ,the sewing heads may be swung upwardly out of. operative position so as to permit ready access to the other mechanism adjacent the stitching point, one of the brackets Y |55 of each pair thereof is provided with a ro tatably mounted lock cam shaft |55,"see Figures 2, 3, is and ia'uponone endet which is e handle |15 and upon the other vc'nd of which a locking cam |1|'is arranged. This cam is adaptedto be engaged in either one of a pair of notches |12 located in an arcuate flange on the cap portion |55 of the bracket. 'Ihus, the locking cam'|1| may be engaged with one of the notches to hold the sewing mechanism in its operative position as illustrated by one of the sewing heads in Figures The bearing' sleeve |15 of shaft |15 extends beyond and to the right of pinion |15 as does a hub portion |55 formed orethis pin- 5 ion. This hub extension |55 extends through an arcuate slot |5| in a slide or sector |52. 'I'he end of shaft |15 is provided with an eccentric crank disk |55 and a crank pin |54 extending therethrough beyond the left'hand 10 Aface of this eccentric crank disk |55 as viewed in A Figure 19, and engages a recess |55 in the hub extension 55 to key or lock the eccentric crank disk to the pinion |15 so that the two will rotate in unison. 15 Pivotally mounted on the crank pin |54 is a needle arm actuating link |55 having the other end thereof pivotally connected as at |51 to a lateral extension |55 on a .needle arm |59. I'his needle arm is pivotally mounted on a pivot pin 20 or projection |55 projecting from the face of the sector or slide |52. Thus, when theA eccentric crank disk |55 is rotated, the crank pin v |54 actuates the needle arm actuating link |55 whichswill rock the needle arm |55 about its 25 pivot to impart a thrusting and retracting movement to the needle |5|r i j Y The slide or sector |52 is moimted for a sliding reciprocating movement by means of a brackeels: fixed te ehesewing heed body le: by 3i?-V means of bolts |55. AThis bracket is provided with an arcuate guideway |54 with which'an intertting portion |55 formed on the upper end of the slide |52 engages The slide |52 is adapted fo'be reciproca@ mE 35 Y its guideway during the thrusting and retracting movement of .the needle and in timed relation thereto and for accomplishing this I provide theeccentric`disk|55 with' a strap |51 which is connee-ted byen er1-iiiV ist with the pivot -m carried 4' by the slide |52 and upon which the needle arm the eccentric crank disk |55 imparts a thrusting Vand retracting movement to the needle |5| and a reciprocating movement in an arcuate path to the slide 52 and consequently to the pivot |55 of the needle arm. This rocks the needle l5| dui-ing its ,thrusting and retractingfmovement because of the movement of the supporting pivot w |55 through angcuate path.

The needle is of arcuate or bowed longitudinal configuration and the needle is reciprocated on an arcuate path about the center |55 which center is shifted on an arcstruck from a point in the arcuate path of the needle. The needle rocks substantially about al point coincident-with the center line of the seam so that irrespective of the rocking movement imparted to the needle. the needle always pierces the fabrics in the same w horizontal plane.

'Ihe rocking movement of the needle is for the purpose of spreading the loop formed thereby and thus provides a positively spread loop having sumcient clearance to-permit the same to be mi-r taken upby the looper which intersects the path of travel of the needle at the end of this rockingmovement. As was previously mentioned. the looper |22 reciprocates in a path or vertical plane arranged'vo at substantially right angles to the path of movement of the needle |5|. The movement of the' -V looper-and needle are so co-related and timed that the point |45 ofthe looper is first recipro-jcated'past the path oft-revel of the needle and is l5 partaking of its return stroke as the needle partakes of its thrusting movement. As the looper is passing the path of the needle, the needle passes over the looper point |48 and through the loop carried by the looper, the needle continuing its forward thrusting movement while the looper continues its movement past the needle path. At this time the point of the needle is rocked in a downward direction to spread the loop formed thereby and during this period and at the commencement of the retracting movement of the needle the looper again moves forward to cross the path of the needle as the needle is being retracted. This rocking movement of the needle immediately prior and during the commencement of its retracting movement has lowered the needle to a point below the horizontal path of the looper and has spread the loop carried by the needle so that as the needle is continuing in its retracting movement, the looper is being thrust forward so that its point |48 passes over the receding point of the needle I9| and through the loop which was formed by the needle. Thisbrieily is the cycle of actions of the needle and looper. 'I'his cycle is graphically illustrated by a comparison of Figures 29 to 37 inclusive. In Figure 29 the needle III is shown in full black lines in its extremely retracted position; Ain full light lines in its fully forward or thrusting position; in dotted lines in ,its intermediate thrusting position; and in dot and dash lines in its intermediate retracting position.

Figure 30 illustrates diagrammatically the relative positions of the looper and needle in the full black line position indicated in Figure 29. This position of the parts is also shown in elevation in Figure 31. 'Ihe relative positions of the needle and looper are diagrammatically shown in Figure 32 corresponding to the dotted line positionl of the needle illustrated in Figure 29. This position of the parts is illustrated in elevation in Figure 33. Figure 34 shows the relative positions of the needle and looper corresponding to the light line podtion illustrated in Figure 29. This position of the parts is illustrated in elevation in Figure 35. The relative positions of the needle and looper are diagrammatically illustrated in Figure 36 corresponding to the dot and dash position of the needle illustrated in Figure 29. This position of the parts is illustrated in elevation in Figure 37.

As shown in Figure 36 the looper |48 is at the end of its forward movement in` which it has been moved past and has intersected the path of travel of the needle |8I. Theneedle III is at the end of its retracting movement and is just about to start its thrusting movement. In Figure 32 the looper is shown intermediate its backward or return movement whereby the loop A formed thereby is being spread by reason of this return movement of the looper. As the end of the looper is about to pass the needle path, the needle is partaking of its thrusting movement and passes through the loop A and continues its forward or thrusting movement to the position illustrated in Figure 34 while the looper |48 continues its return movement to the extreme position illustrated in Figure 34. At this time the loop Aformed by the looper has slipped well onto the needle. The needle then rocks to lower its point and spread the loop B formed thereby and during this rocking movement, the needle commences its retracting movement. The rocking of the needle has lowered the point thereof below the horizontal path of travel of the looper which is partaking of its forward or thrusting movement while the needle is partaking of its retracting movement. Hence, the looper point |48 passes over the needle and through the loop carried thereby so as to take up and hold the needle loop. As the looper commences its retracting movement its loop is again spread and the needle is again partaking 0f its thrusting movement to pass over the looper end and take up the loop being formed thereby. Obviously, this cycle of operations continues so that a single chain lock-stitch such as illustrated in Figures 46 and 47 inclusive is produced.

An important feature of this invention is the construction and arrangement of the sewing head whereby the needle is not only caused to simultaneously partake of a thrusting and retracting movement and a rocking movement but is also so actuated and controlled that it moves at differential speeds, moving slower at the end of its thrusting and retracting movements. At the end of its thrusting movement its movement is retarded to permit the looper to take up the loop formed by the needle and its speed is retarded at the end of its retracting movement so that the needle may be kept out of engagement with the fabrics a maximum length of time. Thus, the speed with which the seam may be sewed is increased because the fabrics will be permitted to travel transversely to the path of the needle without being retarded by the needle during a large portion of each sewing operation.

In order to graphically illustrate this, the path described by the point of the needle has been illustrated in Figure 29 and this path of travel has been divided into I2 increments numbered accordingly and starting with the position of the parts illustrated in light lines in Figure 29, that is with the needle point at the extreme end of its thrusting position. In a like manner the arcuate path' of the pivot I 90 of the needle arm |89 has been indicated and has been divided into a corresponding number of increments. Moreover the circular path of travel of the crank pin |84 has been correspondingly divided and numbered as has the pivotal connection |81 between the needle arm actuating link |86 and the needle arm |88. By particular reference to Figure 29 the construction and arrangement of parts by which this diiIerential movement of the needle is accomplished will be described.

As will be noted by reference to the numbered increments indicating the travel of the point of the needle, the last part of the forward or thrusting movement of the needle and the first part of the retraoting movement of the needle occurs comparatively slowly. The increments numbered 2, 3, 4 and 5 indicate that the movement of the needle from the point 2 to the point 6 which is substantially the end of its retracting movement, occurs relatively rapidly. The increment between the points 6 and l is relatively small indicating that the needle travels relatively slowly at the end of its retracting movement and at the beginning of its thrusting movement whereas the distances between the points l, 8, 8 and I0 indicate that this portion of the forward movement of the neede occurs relatively rapidly. Thus, the needle is thrust through and retracted through the fabrics relatively rapidly but moves more slowly at both ends of its stroke or movement.

The corresponding movement of the crank pin |84, the pivotal connection between the crank arm |86 and the needle arm |89, and the movement of the needle arm pivot I may also be readily ascertained by a comparison of the num- 75 lthe lof the pivot |90.

-loop carried by the,nedl

' 29, this occurs substantially while the crank pin |84 is passing through points Il, Il, |2 and I, and' points 5, 6 yand 1 marked on the circular path of the crank pin.

The shining of the pivot m of me needle arm -will obviously cause a rocking of the needle arm lll, the greatest movement of the needle arm occurring' at the point thereof when the point is partaking of the end of its thrusting movement and the beginning of its retracting movement. The needle is arc-shaped longitudinally,

the center of the arc being struck from the center Thus, by shifting the center of the pivot |90 for instance, toward the left as viewed in Figure '29, the needle point isrocked downwardly, whereas the shifting of the center of this pivot |99 to the right, the needle point is rocked upwardly.- The greatest amount vof movement ofthe center of pivot |99 occurs to the left of a vertical plane passing through the fixed center C so that as a consequence the Vgreatest rocking movement of the needle point occurs at the end of its thrusting movement and at the beginning of its retracting movement as previously described.

This permits of the positive spreading'of the e point so that the loop thusformed may be taken of! the needle by the looper.

The center C referred to is the center aboutv n .rcuate path of the pivot ill is.de

which the l scribed. andthe arcof the needle is described about a center coincident-with the center of the pivot Ill. vAs a consequence irrespective of the rocking movement of the needle, the needle always pierces the fabrics on a horizontal plane passing through the center C and the rocking movement of the needle irrespective of its podtionfduri'ng its thrusting' and retracting movements, rocks about this center pointC.

By reference to Figures 2 and 3 it.will be noted that the threads E supplied to the needles are brought down through guides Ill secured to the frame vpart |55 of themachine and through thread tension devices 2li. The guide and tension device of each set .is preferably mounted upon a bracket livadjustable transversely of the machine by means of a clamping bolt 2|! working in a T-slot 293- formed in the front face of the frame part |55. Thus when thesewing heads and fabric forming devices are adjusted to vary the width of the tubes or plaits, the' thread guides and'tensioning members. may likewise be adjusted. The thread E for each sewing head is passed through an eye 294 formed on the eccentric strap |91 and thence through an-eye 2li on the The thread E then passes through a passage 2li formed in needle arm, see Figure 18, and upwardly through an eye 291 adjacent the point of the needle, see also Figure 18.

'l'he sewingA operation will be best understood by inthethreadTcarriedbytheiooperisillustrated by spaced light lines whereas the thread E carried by the needle is indicatedby a heavy black line.' l

' same time reference to Figures 38 to 45 inclusive, where- As seen in Figure 38, the looper point I of looper |22 is partaking of its return or retracting movement and this retracting movement acts to spread the loop carried by the looper. At the the needle |9| is partaking of its ,5

forward thrusting movement and as shown in Figure 39, has-pierced the tuck or fold S and the adjacent portion L' of the lining fabric L. VThe point'of the needle in Figure 39 has not as yet been rocked downwardly so that its path of travel is above the horizontal piane of the looper-'end |48. Thus, the needle point passes through the loop carried by the looper and as shown in Figure 40, as the looper continues its retracting movement, the needle continues the thrusting movement so as to slide the loop from the looper well onto the needle.v

As viewed in Figure 41,.the needle l9i has rocked downwardly to spread the loop carried thereby and the looper is commencing its for- 2Q ward or thrusting movement again. Byfreason of the downward rocking of the needle point, the

Y needle point has moved below the horizontal path of travel of the looper so that the looper point looper is partaking of its thrusting movement while the needle is of its retracting movement to leave the needle loop on the looper point |48. The needle loop is shown as carried 30 completely by the looper point in Figure 43 and the looper is commencing its 4retracting movement while the needle I9| is again commencing its thrusting movement to enter the fabrics at a point spaced from the point of previous en- 35 trance, this being occasioned by reason of the travel of the work in the direction of the arrow ridge. Y

AsseeninFigureiltheneedle isi hasagain beenthmstthroughtheworkandhasalsobeenso thrust throughthe second loop spread: by reason of the retractlng movement of the looper. Again-the needle point rocks downwardly and the looper moves forwardly to take the nextloop from of! the needle which as shown in Figure 45 is 45 completely retracted. j

This cycle of operations is obviously repeated. and as a result the chain lock-stitch such as illustrated in Figure 46 results. The appearance -of the stitching on the reverse side of th'e fabric is so Villustrated in Figure 4'?.

' From vthe foregoing it is believed that the man- Y ner in which our improved method is"ex ecuted and the operation of our improved sewing mechanismwillbeapparenttothoseskilledinthisss art. Inaccordancewithourmethoditispossible to unite finish and lining fabrics to form tubular plaits in such a manner that the seams or the tubes While the herein described construction has been found to operate entirely satisfactorily in actual practice, the specificform of constnicu completed interiori! 

